Irish: reduced Anglicized form of Gaelic Ó Lochlainn ‘descendant of Lochlann’, a personal name meaning ‘stranger’, originally a term denoting Scandinavia (a compound of loch ‘lake’, ‘fjord’ + lann ‘land’). Many Irish bearers of the name claim descent from Lochlann, a 10th century lord of Corcomroe, County Clare.